Initial 25(OH)D concentrations were in the deficiency range (< 50 nmol/l) and testosterone values were at the lower end of the reference range (9.09-55.28 nmol/l for males aged 20-49 years) in both groups.

Mean circulating 25(OH)D concentrations increased significantly by 53.5 nmol/l in the vitamin D group, but remained almost constant in the placebo group.